Nagios is a powerful, enterprise-class host, service, application, and network monitoring program. Designed to be fast, flexible, and rock-solid stable. Nagios runs on *NIX hosts and can monitor Windows, Linux/Unix/BSD, Netware, and network devices.

Ext2Read is an explorer like utility to explore ext2/ext3/ext4 files. It now supports LVM2 and EXT4 extents. It can be used to view and copy files and folders. It can recursively copy entire folders. It can also be used to view and copy disk and file

ModSecurity is a web application firewall that can work either embedded or as a reverse proxy. It provides protection from a range of attacks against web applications and allows for HTTP traffic monitoring, logging and real-time analysis.

JSmooth creates standard Windows executable files (.exe) that smartly launch java applications. It makes java deployment much smoother and user-friendly, as it is able to find and run Java VMs by itself, or help the user get one if none are available.

DenyHosts is a python program that automatically blocks ssh attacks by adding entries to /etc/hosts.deny.
DenyHosts will also inform Linux administrators about offending hosts, attacked users and suspicious logins.

HTB.init is a shell script derived from CBQ.init that allows for easy setup of HTB-based traffic control on Linux. HTB (Hierachical Token Bucket) is a new queueing discipline which attempts to address the weaknesses of current CBQ implementation.

Pexpect is a Python module for spawning child applications; controlling them; and responding to expected patterns in their output. Pexpect can be used for automating interactive applications such as ssh, ftp, passwd, telnet, etc. Pexpect is pure Python.
Note that Pexpect development has moved to Github: https://github.com/pexpect/pexpect